SS Foil vrs Antioxidation Paste

Tommegow

Tommegow

Joined
Dec 16, 2004
Messages
678
I made a D2 file guide and decided to HT one half with SS Foil and the other half with some Anti-oxidising paste I had purchased.
I also did 2 scrap pieces of Sandvik 13c26
http://community.webshots.com/album/560695762aYltPm
This paste may work with oil hardening steel like satanite
I will try it on some 1084 next
I will use foil for air hardening steels for sure now.
Most of y'all knew that I'll bet.
 
I think that type of experimentation is what teaches you your own preferred methods along the journey, Tom. I agree you should try it on an oil hardening carbon steel, too. Can't beat that foil for any steel you can plate quench.
 
Tom,
Don't feel bad, Im a friggin hard head too!!!:D You knew it wouldn't work well, (because everyone already told you that) but you just had to try it to prove them all right! Oh how many times I've been there!:D:D At least now you know!
Matt
 
I have had the best luck with just using an ultra rich flame. But I pretty much stick to the simple steels except for 5160 and some of the alloy steels.
 
I tried some of the BPC special courtesy of TCMickey. I tried it right along side of a piece in the ss foil. Both pieces of steel where 19C27 from Sandvic. This calls for 1950f for a few minutes and an oil quench. I go the PBC piece to about 750f and held it over a small box while I liberally sprinkled the PBC on with a huge homemade "salt" shaker. I had lots on everywhere, But I think the tip area cooled to much and it didn't stick well. I got pitting there. I think if I had reheated to around 700 of so and recoated the tip area It may have worked better. Maybe it the steel was a bit hotter and you stuck quickly it in a can full of the stuff you could melt on a good coat. IF IF IF you could get on a good coating it would work. It felt and acted like soapstone after I finished heating and quenching. I had to work a bit to remove it. I am makeing a HT oven and I am very seriously thinking of making it as close as possible to air tight and then keeping it full of argon. I get the full meal discount at the welding supply and I believe it it is sealed everywhere but the door joint it should not take that much argon flow to keep the O2 out.
 
ib2v4u said:
I tried some of the BPC special courtesy of TCMickey. I tried it right along side of a piece in the ss foil. Both pieces of steel where 19C27 from Sandvic. This calls for 1950f for a few minutes and an oil quench. I go the PBC piece to about 750f and held it over a small box while I liberally sprinkled the PBC on with a huge homemade "salt" shaker. I had lots on everywhere, But I think the tip area cooled to much and it didn't stick well. I got pitting there. I think if I had reheated to around 700 of so and recoated the tip area It may have worked better. Maybe it the steel was a bit hotter and you stuck quickly it in a can full of the stuff you could melt on a good coat. IF IF IF you could get on a good coating it would work. It felt and acted like soapstone after I finished heating and quenching. I had to work a bit to remove it. I am makeing a HT oven and I am very seriously thinking of making it as close as possible to air tight and then keeping it full of argon. I get the full meal discount at the welding supply and I believe it it is sealed everywhere but the door joint it should not take that much argon flow to keep the O2 out.
Click to expand...

The Argon will displace the O2, therefore I'm not sure that it wouldn't be advantageous to have a small "vent" in the top for a way to displace the
O2??? 4lbs of flow should be more than plenty...
Thoughts?
Matt
 
My argon furnace has a vent on top. Argon is heavier than air.

The door is a tapered wedge that fits up into the cavity. It ain't air tight though. I sit the furnace at an angle, that way the argon covers the parts before it can spill out. I use about 1 CFM, or less, but I'm cheap.

I've mostly moved to foil and PBC. Argon is expensive, and it doesn't prevent oxidation during the quench. I love having bright clean D2 after HT, because my little surface grinder doesn't like hard D2. What did I do before foil...

I've started plate quenching machined parts too. So there's a trick I learned from knife making that I apply to general machine work. Nice.
 
Nathan the Machinist said:
Yes, but I don't think it works well.
Click to expand...

Oh, It made me think because thats what was mentioned near the back of "david boye's step by step knifemaking"

I would think that any gas that is not oxygen would work, provided that no more air diffuses with the low-density nitrogen.
 
Since Nitrogen is the major component of air (78%) its nearly equivalent density means the only way the oxygen can be removed is by dilution, meaning it takes a lot of nitrogen. Argon is much denser than air, meaning it can displace and "push" the air out of the furnace. Takes a lot less gas and works a lot better.

Hope that's clear.
 
''I've mostly moved to foil and PBC. Argon is expensive, and it doesn't prevent oxidation during the quench. I love having bright clean D2 after HT, because my little surface grinder doesn't like hard D2. What did I do before foil...''

Is this why you quench in the foil and remove it first?
 
fludunlimited said:
''I've mostly moved to foil and PBC. Argon is expensive, and it doesn't prevent oxidation during the quench. I love having bright clean D2 after HT, because my little surface grinder doesn't like hard D2. What did I do before foil...''

Is this why you quench in the foil and remove it first?
Click to expand...


Yes, and the foil is not slowing down a plate quench very much. Plate quenching works great through foil, though an air quench wouldn't. So, for the cleanest parts, I quench with foil on the parts. If I had irregular parts that don't lend themselves to plate quench, I'd heat in argon and air quench and tumble or grind the little bit of scale off. But sometimes my little grinder doesn't do well on hard D2, it is a dry grinder.

Foil is cheep and 50 feet is gonna last you a long time. I use the high temp stuff (309), because D2 is a bit above the range of the regular stuff, and I'm not gonna risk a $1,000 machined part. But plenty of folks use the regular stuff to 2000F and beyond.

I make an envelope. First I cut off a piece of foil. I fold in in half. I fold over a seam on an edge, about an inch. Then I fold that seam again in half. I use a roller to keep the seams tight. Then I do the other side. Then I put the part in. Then I cut myself on the foil and find gloves. Then I double seam the end. Then I shake the envelope around until the part is centered and kinda squeeze around it to hold it in place, wouldn't want a thick seam to hold the plate off the part in a spot during quench.

You're supposed to quench with thick aluminum plates, but I use heavy thick steel plates. It is still way faster cooling than air quench, and as Kevin has pointed out, there is no point quenching faster than the TTT nose for your steel indicates. Though I'm not sure that's the whole story.
 
I understand that with argo I would have O2 from the time I open the door till the blade hits the oil. You see I am using 19C27 and plan keep using it as my stainless material. Sandvic calls for a 3 minute soak at 1950f and oil quench. How much scale will I get in the time from oven to oil???. I did the foil and the steel came seemed to come out great. Had the foil tightly on piece and was going to rip off but it is not easy to do rapidly so went from oven to oil with the foil. That is why I think I want to try the argon, I agree that a low flow of 1cfm from the top rear should be fine. Thoughts?????
 
ib2v4u said:
I understand that with argon I would have O2 from the time I open the door till the blade hits the oil. You see I am using 19C27 and plan keep using it as my stainless material. Sandvic calls for a 3 minute soak at 1950f and oil quench. How much scale will I get in the time from oven to oil???.
Click to expand...

Not enough to worry about unless you're doing an air quench. BTW, if you're not using a good quality quenching oil, the burned on oil is a real pain.
 
I have some parks so hopefully that won't be that much of a problem. I have all the pieces to redo my oven now. Just need to get to the steel yard and pick up a piece of 8 or 10 gauge to make the case with. Then I can go back to HTing. Jim
 
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